JupyterLab

4.5.7

(Full Changelog)

Security patches

The details of advisories are under embargo until JupyterLab and Notebook releases land on supported distribution channels.

• CVE-2026-42557 https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-mqcg-5x36-vfcg
• CVE-2026-42266 https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-37w4-hwhx-4rc4
• CVE-2026-40171 https://github.com/jupyter/notebook/security/advisories/GHSA-rch3-82jr-f9w9

Bugs fixed

• Video and Audio Content Providers: Fix JupyterLite support #18652 (@martinRenou)
• Fix notebook hang when dropping cells #18808 (@MUFFANUJ)
• Fix Contextual Help keyboard shortcut reliability and menu Help functionality #18747 (@itsmejay80)
• Fix focusing input element when opening a dialog from Command Palette #18735 (@Carreau)
• Fix native context menu blocked even when context menu is suppressed #18753 (@utsav-develops)
• Fix flaky toolbar item placement in popup #18618 (@filipeoliveira05)
• Update terminal default font family to honor macOS system-wide ui-monospace #18647 (@flaviomartins)

Maintenance and upkeep improvements

• Fix linting issue #18819 (@krassowski)
• Fix syntax for Python 3.9 on 4.5.x branch #18817 (@krassowski)
• Remove unused CodeMirror v5 CSS rule #18785 (@Carreau)
• Remove unused CSS rule forgotten after CodeMirror migration #18763 (@Carreau)
• Remove unused progress bar CSS rule in execution indicator #18759 (@Carreau)
• Remove dead .jp-VariableRenderer-TrustButton CSS rule #18762 (@Carreau)
• Remove used .jp-Cell-Placeholder CSS rules #18761 (@Carreau)

Documentation improvements

• Fix name of option for extension manager implementation in docs #18788 (@krassowski)
• Remove 4.5.0 announcement from docs #18740 (@krassowski)

Contributors to this release

The following people contributed discussions, new ideas, code and documentation contributions, and review.
See our definition of contributors.

(GitHub contributors page for this release)

@Carreau (activity) | @filipeoliveira05 (activity) | @flaviomartins (activity) | @itsmejay80 (activity) | @jtpio (activity) | @krassowski (activity) | @martinRenou (activity) | @MUFFANUJ (activity) | @utsav-develops (activity)